Fig. 6. Differential accumulation of 21 and 25 nt antisense RNAs during vegetative growth of silenced strains. Low-molecular weight RNAs were isolated from a silenced albino transformant of plasmid pMAT647 (a3), grown for different times (hours) in liquid culture and from spores collected from solid medium. Fifteen micrograms of RNA was loaded in each lane. Ten picomoles per lane of 29-mer DNA oligonucleotide in antisense orientation (AS) and 25-mer DNA oligonucleotide in sense orientation (S) were used as size markers. (A) RNA blot hybridized with a carB antisense-specific riboprobe (Figure 1A, probe a′). The predominant RNA species in the small RNA samples (sRNA) were stained with EtBr after RNAs were separated by agarose gel electrophoresis. (B) Identical RNA blot hybridized with a carB sense-specific riboprobe (Figure 1A, probe a).